Type of sport is related to injury profile: a study on cross country skiers, swimmers, long-distance runners and soccer players. A retrospective 12-month study

Swimming for low back pain: A scoping review

BACKGROUND

Guidelines recommend exercise for treatment of chronic low back pain and prevention, but the amount and quality of evidence for different exercise modes is highly variable. Swimming is commonly recommended by health professionals, but the extent and quality of research supporting its relationship with back pain is not clear.

OBJECTIVES

The aim of this scoping review was to map the extent, characteristics and findings of research investigating the relationship between swimming and low back pain.

DESIGN

Scoping review.

METHOD

Four electronic databases (MEDLINE, EMBASE, CINAHL, and SPORT Discus) were searched from inception to February 2023. We included primary studies and reviews that reported an association between swimming and low back pain. Hydrotherapy studies were excluded.

RESULTS

3093 articles were identified, and 44 studies included. Only one randomised controlled trial and one longitudinal cohort study were included. Most studies were cross-sectional (37/44; 84.1%), included competitive athletes (23/39; 59.0%), and did not primarily focus on the association between swimming and low back pain in the aims (41/44; 93.2%). Instead, most data available were largely incidentally collected or a secondary outcome. The reported associations between swimming and low back pain were highly variable regardless of whether the comparison was to other sports (odds ratio: 0.17 to 17.92) or no sport (odds ratio: 0.54 to 3.01).

CONCLUSION

Most available literature investigating swimming and low back pain is cross-sectional in design. We did not identify any clear pattern of association between swimming and low back pain, based on the available literature.

The associated factors for physical activity-related injuries among first-year university students in southern China from a biopsychosocial perspective

Background

Understanding the diverse factors influencing physical activity-related injuries is crucial for developing effective interventions that enable individuals to participate in physical activity (PA) while minimizing injury risk. Currently, research evidence on the multiple factors associated with PA-related injuries is inadequate. This study aimed to examine the associations between PA-related injuries and various biological, psychological, and social factors among first-year university students in China.

Methods

We recruited first-year university students from Shantou University in Guangdong Province, China, to participate in our study. Data collection employed a structured self-administered questionnaire, gathering information on PA-related injuries, as well as relevant biological, psychological, and social factors. Binary logistic regression, using a stepwise modeling approach, was employed for the data analysis.

Results

Among 1,051 first-year university students, 28.16% reported having experienced PA-related injuries in the past year. Most of the injuries reported were minor, with the knee or lower leg being the most frequently injured part of the body. Improper posture, environmental conditions, and excessive physical load were the leading causes of PA-related injuries. Multiple logistic regression analysis revealed that female students (OR = 0.67, 95% CI: 0.47-0.94, p = 0.022) had reduced odds of PA-related injuries. Conversely, high neuroticism (OR = 1.61, 95% CI: 1.07-2.41, p = 0.022), being a member of a sports team (OR = 2.09, 95% CI: 1.34-3.27, p < 0.001), PA on the wet ground (OR = 1.73, 95% CI: 1.18-2.54, p = 0.005) increased the odds of PA-related injuries.

Conclusion

Our findings underscore the intricate interplay of various factors contributing to PA-related injuries. Identifying high-risk individuals based on physiological and psychological characteristics, coupled with targeted interventions addressing modifiable risk factors, is crucial for effective prevention.

Knee joint repositioning error in different trunk positions among females with chronic nonspecific low back pain: A cross-sectional study

PURPOSE

Proprioception is a self-perceived sense of position and movement of one's body and its deficits can lead to motor control problems such as delayed muscle reflexes. Previous studies have confirmed lumbar proprioception impairments among individuals with Low Back Pain (LBP), which can afflict the normal central sensory-motor control and hence increases the risk of abnormal loading on the lumbar spine. Although the local investigation of proprioception is important, its influence on other joints in a kinetic chain particularly between extremities and spine should not be ignored. Therefore, the aim of this study was to compare the proprioception of knee joint in different trunk positions among females with chronic nonspecific low back pain (CNSLBP) and healthy females.

DESIGN

The study included 24 healthy subjects and 25 patients with CNSLBP participated in this study. Repositioning error of knee joint in four different lumbar positions including flexion, neutral position, 50% ROM of left rotation and 50% ROM right rotation was evaluated using an inclinometer. Absolute error and constant error were obtained and analyzed.

RESULTS

Absolute error in flexion and neutral positions in the individuals with CNSLBP were significantly higher than in healthy individuals; whereas, there was no significant difference in absolute and constant error between the two groups in 50% rotation to either side.

CONCLUSION

This study showed that knee joint repositioning accuracy was reduced in patients with CNSLBP compared to healthy ones.

Injuries and Illnesses During the 53rd FIS Nordic World Ski Championships 2021 in Oberstdorf: A Prospective Cohort Study

OBJECTIVE

For the 3 Nordic ski disciplines of cross-country skiing, Nordic combined, and ski jumping, data on injuries and illnesses during major sporting events only exist from the Winter Olympics of 2010 to 2018. So far, an investigation has not been conducted during the Nordic World Ski Championships.

DESIGN

Prospective cohort study.

SETTING

Fédération Internationale de Ski (FIS) Nordic World Ski Championships 2021 in Oberstdorf, Germany.

PARTICIPANTS

Overall, 663 athletes from 65 nations participated in the FIS Nordic World Ski Championships 2021. The study population included 344 athletes from 32 nations.

INTERVENTIONS

National medical teams were invited to report daily all newly incurred or exacerbated injuries and illnesses.

MAIN OUTCOME MEASURES

All reported injuries and illnesses that occurred during the championships from February 23 until March 7, 2021, were analyzed. Injury and illness rates were calculated with 95% confidence intervals (95% CIs).

RESULTS

The 32 reporting nations returned 88.4% of the daily report forms. The incidence of injuries was 4.7 (95% CI, 2.4-6.9) per 100 athletes in the 3 Nordic ski disciplines. The incidence of illness was also 4.7 (95% CI, 2.4-6.9) per 100 athletes with a relative proportion of infection-related illnesses of 31.3%.

CONCLUSIONS

Although the incidence of injuries of the Nordic disciplines was comparable with those of the 2010 to 2018 Winter Olympics, the incidence of illnesses was lower than during the previous 3 Winter Olympic Games with a lower rate of infection-related illnesses. This might be caused by the high hygiene measures due to the coronavirus disease 2019 pandemic.

Health problems in national team cross-country skiers over a competitive season: a 17-week prospective cohort study

OBJECTIVE

Few long-term prospective studies have investigated health problems in elite competitive cross-country (XC) skiers. Hence, our objective was to compare the prevalence of health problems in national team XC skiers over a competitive season.

METHODS

Forty national team XC skiers participated in this prospective, observational study. Two groups were characterised according to performance level: senior (n=18, ~26 years old, 9 women) and development (n=22, ~21 years old, 9 women). The skiers reported all and substantial injuries and illnesses weekly for 17 consecutive weeks throughout the 2019/2020 competitive season using the Oslo Sports Trauma Research Center Questionnaire on Health Problems.

RESULTS

The average weekly prevalence of all and substantial health problems was 19% (95% CI: 16% to 22%) and 12% (95% CI: 9% to 15%), respectively, and was similar between senior and development level skiers (p>0.05). The injury prevalence was higher in senior versus development level skiers (12%, 95% CI: 9% to 15% vs 5%, 95% CI: 3% to 7%; p<0.001), while illnesses were less common (8%, 95% CI: 3% to 13% vs 13%, 95% CI: 9% to 17%, respectively; p=0.031). Illnesses accounted for 72% of all problems. The prevalence of all health problems was higher in female than in male skiers (23%, 95% CI: 19% to 27% vs 15%, 95% CI: 11% to 19%; p<0.003).

CONCLUSIONS

Health problems, especially illnesses, were relatively common, with approximately one in five skiers (19%) reporting at least one problem in any given week. Both performance level and sex influenced the prevalence of different types of health problems.

International survey of injury surveillance practices in competitive swimming

OBJECTIVE

The purpose of this study was to identify the injury surveillance practices being used in competitive swimming environments. It explored the nature of the data collected, the injury definitions used and the perceived effectiveness of injury surveillance. Finally, this study also examined barriers to injury surveillance.

DESIGN

Online cross-sectional.

PARTICIPANTS

Twenty-two responders working in competitive swimming.

OUTCOME MEASURES

Injury surveillance methods, data collected, perceived level of effectiveness and barriers associated with injury surveillance.

RESULTS

Fifteen responders participated in injury surveillance, with 13 responders using a recognised definition for injury. Ten responders did not use any sports injury classification system. Ten responders found injury surveillance to be very effective at identifying injury trends, while previous injury history and training load data were perceived to be most influential in preventing injury. Limited time, funding and compliance were common obstacles, while poor staff communication and engagement were barriers to the effective implementation of injury surveillance.

CONCLUSIONS

The implementation of injury surveillance is related to the system objectives, competitive level of those under surveillance and the resources available. This implementation requires the balance of adhering to the principles outlined in prominent consensus statements and overcoming the barriers associated with implementing a system effectively.

Sports Injuries Among Players of the Polish National Team in Amputee Football in the Annual Training Cycle

The aim of the study was to determine the frequency, type and origin of the occurrence of injuries in amputee football. The studied group comprised all members of the Polish national amputee football team (n = 25). During the 9-month observation period, 13 players incurred 22 injuries. The incidence proportion was 48.0 per 100 athletes (95% Cl, 28.4-67.6) and the incidence rate was 5.73 per 1000 athlete-days (95% Cl, 3.33-8.12). The study showed that 32.8% of the injuries were to the thigh, 13.6% to the ankle, and 9.1% to the knee. The obtained results indicate that amputee football players rather frequently incur play-related injuries, but a single athlete incurs relatively few of them, with the lower limb being most commonly injured.

Musculoskeletal Injuries in Cross-Country Skiing

Cross-country skiing, one of the oldest forms of skiing, is enjoyed widely as a recreational activity and as a competitive sport. It is practiced in regions with snow-covered landscapes, particularly in the Nordic countries and with increasing popularity in non-Nordic countries of Europe as well as in the United States, Canada, Australia, and New Zealand, among others. Cross-country skiing is a fairly safe activity, and historically the risk of injury has been relatively low. However, advances in equipment development, together with increasing speeds, more demanding trails, and growing numbers of participants, have all contributed to a larger report of injuries, although still comparatively low versus other skiing modalities. Injuries in cross-country skiing can occur either after a single traumatic event or in the setting of chronic repetitive microtrauma (i.e., overuse injuries).

The Disturbing Effect of Neuromuscular Fatigue on Postural Control Is Accentuated in the Premenstrual Phase in Female Athletes

This study explored the fatigue effect on postural control (PC) across menstrual cycle phases (MCPs) in female athletes. Isometric maximal voluntary contraction (IMVC), the center of pressure sway area (CoParea), CoP length in the medio-lateral (CoP_LX) and antero-posterior (CoP_LY) directions, and Y-balance test (YBT) were assessed before and after a fatiguing exercise during the follicular phase (FP), mid-luteal phase (LP), and premenstrual phase (PMP). Baseline normalized reach distances (NRDs) for the YBT were lower (p = 0.00) in the PMP compared to others MCPs, but the IMVC, CoParea, CoP_LX, and CoP_LY remained unchanged. After exercise, the IMVC and the NRD decrease was higher at PMP compared to FP (p = 0.00) and LP (p = 0.00). The CoParea, CoP_LX, and CoP_LY increase was higher in the PMP compared to FP (p = 0.00) and LP (p = 0.00). It was concluded that there is an accentuated PC impairment after exercise observed at PMP.

The effect of motor control training according to the Kinetic Control concept on the back pain of female football players

BACKGROUND

Due to a significant burden associated with training sessions and matches, female football players often suffer from lumbar pain. Physical exercise is considered an effective form of therapy for this condition. The exercises in the Kinetic Control concept are one of the forms of motor control training.

OBJECTIVE

The aim of the study was to evaluate the effectiveness of motor control training according to the Kinetic Control concept on the level of lumbar spine pain, degree of disability, functional level and load distribution of lower limbs in football players.

METHODS

The study included 18 football players, randomly divided into two study groups: A - female players implementing their training plan with additional Kinetic Control training (n= 9) and B (control) - female players implementing their training plan only (n= 9). Pain intensity was measured using Visual Analogue Scale (VAS) and Laitinen's questionnaire. Functional disability was assessed using Oswestry Disability Index (ODI) and Back Pain Functional Scale (BPFS). The asymmetry index was assessed in a balance test with open and closed eyes and a countermovement jump (CMJ).

RESULTS

There was a significant statistical difference between the groups (p< 0.05) in measurements using VAS, ODI and BPFS, in favor of group A. Asymmetry index values in tests on the dynamometer platform did not differ significantly between the groups (p> 0.05). A statistically significant correlation was found between the asymmetry index score in the closed-eye balance test (r= 0.567, p= 0.049) and the CMJ landing phase (r= 0.641, p= 0.033), and the level of pain measured using VAS.

CONCLUSIONS

Motor control training in the Kinetic Control concept reduced the pain symptoms of the lumbar spine and the degree of disability and increased the functional level in football female players.

A systematic review of running-related musculoskeletal injuries in runners

OBJECTIVE

Running-related musculoskeletal injuries (RRMIs), especially stemming from overuse, frequently occur in runners. This study aimed to systematically review the literature and determine the incidence and prevalence proportion of RRMIs by anatomic location and specific pathology.

METHODS

An electronic database search with no date beginning restrictions was performed in SPORTDiscus, PubMed, and MEDLINE up to June 2020. Prospective studies were used to find the anatomic location and the incidence proportion of each RRMI, whereas retrospective or cross-sectional studies were used to find the prevalence proportion of each RRMI. A separate analysis for ultramarathon runners was performed.

RESULTS

The overall injury incidence and prevalence were 40.2% ± 18.8% and 44.6% ± 18.4% (mean ± SD), respectively. The knee, ankle, and lower leg accounted for the highest proportion of injury incidence, whereas the knee, lower leg, and foot/toes had the highest proportion of injury prevalence. Achilles tendinopathy (10.3%), medial tibial stress syndrome (9.4%), patellofemoral pain syndrome (6.3%), plantar fasciitis (6.1%), and ankle sprains (5.8%) accounted for the highest proportion of injury incidence, whereas patellofemoral pain syndrome (16.7%), medial tibial stress syndrome (9.1%), plantar fasciitis (7.9%), iliotibial band syndrome (7.9%), and Achilles tendinopathy (6.6%) had the highest proportion of injury prevalence. The ankle (34.5%), knee (28.1%), and lower leg (12.9%) were the 3 most frequently injured sites among ultramarathoners.

CONCLUSION

The injury incidence proportions by anatomic location between ultramarathoners and non-ultramarathoners were not significantly different (p = 0.798). The pathologies with the highest incidence proportion of injuries were anterior compartment tendinopathy (19.4%), patellofemoral pain syndrome (15.8%), and Achilles tendinopathy (13.7%). The interpretation of epidemiological data in RRMIs is limited due to several methodological issues encountered.

Vascular adaptations in nonstimulated areas during hybrid cycling or handcycling in people with a spinal cord injury: a pilot study of 10 cases

STUDY DESIGN

Sub-study of a randomized controlled trial.

OBJECTIVES

To examine if hybrid cycling (cycling with the legs via electrical stimulation combined with voluntary handcycling) compared to handcycling leads to different systemic vascular adaptations in individuals with a long-term spinal cord injury (SCI).

SETTING

Two rehabilitation centers in the Netherlands.

METHODS

Ten individuals with a SCI trained on a hybrid bicycle (N = 5) or a handcycle (N = 5) for 16 weeks twice a week. Prior to and following the training the intima media thickness (IMT) of the common coronary artery (CCA) and superficial femoral artery (SFA) were measured and the flow-mediated dilation (FMD) of the brachial artery (BA) was analyzed.

RESULTS

Before training, there were no significant differences in any of the outcome measures between the groups. We found no change in CCA IMT (pre: 0.616 mm, post: 0.586 mm), or in SFA (pre: 0.512 mm, post: 0.520 mm) after hybrid cycling. We also found no change in FMD % of BA after hybrid cycling (pre: 9.040%, post: 9.220%). There were no changes in CCA IMT, SFA IMT, and FMD% after handcycling either.

CONCLUSIONS

It appears that 16 weeks of twice-weekly training of up to 30 min on a hybrid bicycle or handcycle does not lead to systemic vascular adaptations. A larger sample size and training protocol with more frequent and higher intensity training (which might involve a home-based setting and an adapted period prior to the training) might show different results.

The relationship between training load and pain, injury and illness in competitive swimming: A systematic review

BACKGROUND

Research suggests that the frequency of training, combined with the repetitive motion involved in high volume swimming can predispose swimmers to symptoms of over-training. The prevention of pain, injury and illness is of paramount importance in competitive swimming in order to maximise a swimmer's ability to train and perform consistently. A significant factor in the prevention of pain, injury or illness is the appropriate load monitoring and management practices within a training programme.

OBJECTIVE

The purpose of this systematic review is to investigate the relationship between training load and pain, injury and illness in competitive swimmers.

METHODS

The databases SPORTDiscus, CINAHL, Scopus, MEDLINE and Embase were searched in accordance with PRISMA guidelines. Studies were included if they reported on competitive swimmers and analysed the link between training load and either pain, injury or illness. The methodological quality and study bias were assessed using the Joanna Briggs Institute Critical Appraisal Checklist.

RESULTS

The search retrieved 1,959 articles, 15 of which were included for review. The critical appraisal process indicated study quality was poor overall. Pain was the most explored condition (N = 12), with injury (N = 2) and illness (N = 1) making up the remaining articles. There was no evidence of an association between training load and pain, while there may be some evidence to suggest a relationship between training load and injury or illness.

CONCLUSIONS

The relationship between training load and pain, injury or illness is unclear owing to a host of methodological constraints. The review highlighted that youth, masters and competitive swimmers of a lower ability (e.g. club versus international) may need particular consideration when planning training loads. Winter periods, higher intensity sessions and speed elements may also need to be programmed with care. Monitoring practices need to be developed in conjunction with consensus guidelines, with the inclusion of internal training loads being a priority. Future research should focus on longitudinal prospective studies, utilising the session Rating of Perceived Exertion (sRPE) monitoring method and investigating the applicability of Acute/Chronic Workload Ratio (ACWR) and exponentially weighted moving average (EWMA). Improved methods and study design will provide further clarity on the relationship between load and pain, injury, and illness.

Gender-specific physical activity-related injuries and risk factors among university students in China: a multicentre population-based cross-sectional study

OBJECTIVES

Data on the problem of physical activity-related injury (PARI) in university students and the risk factors for PARI among different genders are rare. We conducted a multicentre population-based study to investigate the occurrence of PARI and to explore the gender-specific risk factors for PARI among Chinese university students.

DESIGN

Cross-sectional study.

PARTICIPANTS

A total of 5341 students in grades 1-3 at eight universities in four Chinese cities were selected to complete the online questionnaires during March and April 2017. The questionnaires assessed sociodemographic characteristics, physical activity PA) involvement, sleep duration, sedentary behaviour and PARI experiences in the past 12 months.

MAIN OUTCOME MEASURES

PARI during the past 12 months.

RESULTS

Among the 5341 participants, 1293 suffered from at least one PARI in the past 12 months, with an overall incidence rate of 24.2% (males: 26.2%, females: 23.2%) and an injury risk of 0.38 injuries/student/year (males: 0.48, females: 0.32). Over half of the injured (57.3%) experienced a withdrawal time of PA and nearly two-fifths (39.6%) required medical attention. Irrespective of gender, Shantou and Xi'an students, sports team members and those who engaged in sports and leisure-time vigorous-intensity PA (VPA) at a higher frequency were more likely to suffer from PARI. Male students who participated in sports and leisure-time VPA for long durations had a greater likelihood of sustaining PARI, while having a chronic condition and being involved in sports and leisure-time moderate-intensity PA at a higher frequency and longer duration were potential contributors to PARI among females.

CONCLUSIONS

The occurrence of PARI and its risk factors differed by gender, which provides a direction towards developing targeted and effective gender-specific preventative programmes to protect Chinese university students from PARI.

Sex Differences in Human Ankle Stiffness During Standing Balance

The purpose of this study is to quantify sex differences in 2-dimensional (2D) ankle stiffness during upright standing balance and investigate the mechanisms for the differences. A dual-axis robotic platform, capable of perturbing the ankle and measuring the corresponding ankle torques in both the sagittal and frontal planes, was used to reliably quantify the 2D ankle stiffness while healthy young human subjects perform a range of standing balance tasks, specifically, ankle muscle co-contraction tasks, weight-bearing tasks, and ankle torque generation tasks. In all task conditions and in both planes of ankle motion, ankle stiffness in males was consistently greater than that in females. Among all 26 experimental conditions, all but 2 conditions in the frontal plane showed statistically significant sex differences. Further investigation on the normalized ankle stiffness, scaled by weight times height, suggests that while sex differences in ankle stiffness in the sagittal plane could be explained by sex differences in anthropometric factors as well as neuromuscular factors, the differences in the frontal plane are mostly explained by anthropometric factors. This study also demonstrates that the sex differences in the sagittal plane were significantly higher as compared to those in the frontal plane. The results in this study will provide a foundation for not only characterizing sex differences in ankle stiffness during locomotion, but also investigating sex differences in lower body stability and risk of ankle injury.

The Masters athlete in Olympic weightlifting: Training, lifestyle, health challenges, and gender differences

Background

Olympic weightlifting requires strength, speed, and explosive power. Vigorous physical activity such as Olympic weightlifting, for older adults has many benefits from improved strength, social interactions, and a healthy and independent lifestyle. Little is known about the training habits, health, and lifestyle of Masters weightlifters that includes top level athletes as well as beginners, and there is a dearth of data on women.

Objectives

The primary aim was to describe demographics, training habits, and health including prevalence of injury and chronic disease in male and female Masters athletes in Olympic weightlifting. The secondary aim was to study gender differences and the age and impact of menopause on participation in the sport.

Results

The 958 participants (46% men), ages 34 to 87, mostly train 3 to 4 days per week in 1 to 2 hour sessions. This is a highly educated and affluent group, 84% are white, 72% are married, 85% are post-secondary graduates. Exercise can also increase the risk of injury compared to less active older adults, but the rates of injury in weightlifting affecting training are lower than seen in other sports. The prevalence of depression and mental health is similar to a general population. Stress levels and sleep disturbances are more common among women than men. Women reach menopause at a similar age as women in industrialized countries, but menopausal symptoms constrained the training.

Conclusion

Older athletes are capable of rigorous training programs and top performances while adjusting to changes due to biological aging. Weightlifting athletes, coaches, and health professionals must be aware of patterns of injuries and gender differences to incorporate successful prevention strategies. Knowledge of presentations of menopause and impact of menopausal symptoms on training allows women and health care providers to make informed treatment decisions.

An Updated Review of the Epidemiology of Swimming Injuries

OBJECTIVE

To carry out a systematic review to update the scientific evidence on the incidence and prevalence of injuries in the swimming discipline, as well as the location, type, and mechanism of the injuries, and to assess whether studies are meeting methodological recommendations for data collection and injury surveillance. TYPE: Analytical-Systematic review.

LITERATURE SURVEY

The databases of PubMed and Sportdiscus were used to search for studies that describe the epidemiology of injuries in adult swimmers between 2010 and March 2020.

METHODOLOGY

Of the 864 articles identified, 14 studies were finally included in this review. The methodological quality of the studies was analyzed with the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) scale and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed.

SYNTHESIS

The results showed a high prevalence of shoulder, knee, and lower back injuries among swimmers due to overuse. These injuries were mainly short-term tendon muscles; there were reported data differences between genders.

CONCLUSIONS

Despite the publication of an injury surveillance single and multisport events document and a consensus on data collection and injury surveillance in swimming, there are huge methodological limitations that do not allow firm conclusions. As such, more epidemiological studies following guidelines for data collection and injury surveillance are needed to establish differences by gender, age group, and swimming stroke.

An Epidemiological look into Hamstring Injuries in the Jamaican Athletic Population

Objective: To take an epidemiological look into hamstring injuries in Jamaican athletes presenting to the University of the West Indies (UWI) Sport Medicine Clinic between 2007 and 2016. The research focused on the contribution of certain demographics and types of sports and activities to the classification, recovery and recurrence of these injuries. Methods: A retrospective chart review was conducted on all the athletes who presented to the UWI Sports Medicine Clinic between 2007 and 2016. An electronic data extraction sheet was used for data collection. The target population consisted of athletes from 13 to 25 years of age who participated in competitive sports at the time of injury. Results: Of the 125 dockets reviewed, 92 were males (73.6%), 30 were females (24%) and three were of unknown sex (2.4%). In summary, 62.4% of the injuries occurred in the 17-21 years age group, 24.8% in the 22-25 years age group and 12.8% in the 13-16 years age group. Seventy-six percent of injuries occurred in Track athletes. Running/sprinting activities were culpable for most of the injuries (42%). Of the 134 injuries, 15.7% were low, 7.5% occurred in the muscle belly, 4.5% were high and the others were unspecified. Fifteen athletes (11.2%) had subsequent recurrences with the highest recurrence rate amongst Track & Field athletes. Only 3 of 21 low injuries and 1 of 6 high injuries recovered within 6 weeks. Conclusion: Hamstring injuries are common in Jamaican athletes with a significant male preponderance. Track & Field athletes, those in the 17 to 21 years age group and those engaging in running or sprinting activities were more likely to sustain injuries. It was difficult to compare the recovery rates of high and low injuries and recurrence rates were found to closely match those in current literature.

Deep learning approach for prediction of impact peak appearance at ground reaction force signal of running activity

Protruding impact peak is one of the features of vertical ground reaction force (GRF) that is related to injury risk while running. The present research is dedicated to predicting GRF impact peak appearance by setting a binary classification problem. Kinematic data, namely a number of raw signals in the sagittal plane, collected by the Vicon motion capture system (Oxford Metrics Group, UK) were employed as predictors. Therefore, the input data for the predictive model are presented as a multi-channel time series. Deep learning techniques, namely five convolutional neural network (CNN) models were applied to the binary classification analysis, based on a Multi-Layer Perceptron (MLP) classifier, support vector machine (SVM), logistic regression, k-nearest neighbors (kNN), and random forest algorithms. SVM, logistic regression, and random forest classifiers demonstrated performances that do not statistically significantly differ. The best classification accuracy achieved is 81.09% ± 2.58%. Due to good performance of the models, this study serves as groundwork for further application of deep learning approaches to predicting kinetic information based on this kind of input data.

Factors Influencing the Relationship Between the Functional Movement Screen and Injury Risk in Sporting Populations: A Systematic Review and Meta-analysis

BACKGROUND

Studies investigating the association between the Functional Movement Screen (FMS) and sports injury risk have reported mixed results across a range of athlete populations.

OBJECTIVES

The purpose of this systematic review was to identify whether athlete age, sex, sport type, injury definition and mechanism contribute to the variable findings.

STUDY DESIGN

Systematic review and meta-analysis.

METHODS

A systematic search was conducted in October 2018 using PubMed, EBSCOhost, Scopus, EmBase and Web of Science databases. Studies were included if they were peer reviewed and published in English language, included athletes from any competition level, performed the FMS at baseline to determine risk groups based on FMS composite score, asymmetry or pain, and prospectively observed injury incidence during training and competition. Study eligibility assessment and data extraction was performed by two reviewers. Random effects meta-analyses were used to determine odds ratio (OR), sensitivity and specificity with 95% confidence intervals. Sub-group analyses were based on athlete age, sex, sport type, injury definition, and injury mechanism.

RESULTS

Twenty-nine studies were included in the FMS composite score meta-analysis. There was a smaller effect for junior (OR = 1.03 [0.67-1.59]; p = 0.881) compared to senior athletes (OR = 1.80 [1.17-2.78]; p = 0.008) and for male (OR = 1.79 [1.08-2.96]; p = 0.024) compared to female (OR = 1.92 [0.43-8.56]; p = 0.392) athletes. FMS composite scores were most likely to be associated with increased injury risk in rugby (OR = 5.92 [1.67-20.92]; p = 0.006), and to a lesser extent American football (OR = 4.41 [0.94-20.61]; p = 0.059) and ice hockey (OR = 3.70 [0.89-15.42]; p = 0.072), compared to other sports. Specificity values were higher than sensitivity values for FMS composite score. Eleven studies were included in the FMS asymmetry meta-analysis with insufficient study numbers to generate sport type subgroups. There was a larger effect for senior (OR = 1.78 [1.16-2.73]; p = 0.008) compared to junior athletes (OR = 1.21 [0.75-1.96]; p = 0.432). Sensitivity values were higher than specificity values for FMS asymmetry. For all FMS outcomes, there were minimal differences across injury definitions and mechanisms. Only four studies provided information about FMS pain and injury risk. There was a smaller effect for senior athletes (OR = 1.28 [0.33-4.96]; p = 0.723) compared to junior athletes (OR = 1.71 [1.16-2.50]; p = 0.006). Specificity values were higher than sensitivity values for FMS pain.

CONCLUSION

Athlete age, sex and sport type explained some of the variable findings of FMS prospective injury-risk studies. FMS composite scores and asymmetry were more useful for estimating injury risk in senior compared to junior athletes. Effect sizes tended to be small except for FMS composite scores in rugby, ice hockey and American football athletes.

PROTOCOL REGISTRATION

CRD42018092916.

Physical activity-related injuries of college students in southern China: A 1-year prospective study

This prospective study was to describe the incidence and characteristics of physical activity-related injuries (PARI) among college students in southern China. Online questionnaires and telephone interviews were combined to investigate the physical activity (PA) participation and PARI occurrences every two weeks. Totally, 84 college students (men: 49; women: 35) with a mean age of 19.4 years completed the entire 1-year follow-up. Overall, 14250.3 PA exposure hours were collected and 36 PARI episodes were reported by 26 students, with an injury incidence density of 2.53 injuries per 1000 PA exposure hours and an injury risk of 0.43 injuries/student/year. July to September accounted for a highest proportion of injuries and half of the injuries happened in the evening. The majority of injuries occurred outdoors, happened in non-contact activities, were acute and involved the lower limbs, with sprains and strains being the primary injury types. Of all injuries, 80.6% resulted in PA withdrawal immediately and 58.3% led to absence from the next planned PA. No significant difference was found between men and women. This study reveals the problem of PARI among college students, which provides the direction for the prevention of PARI in this population.

Epidemiology of physical activity-related injuries in Chinese university students

Knowledge gaps of the physical activity-related injury (PARI) problem among general undergraduates exist. We conducted a study in four universities, where 1421 students graded 1-3 were interviewed face-to-face during April and May after their completion of the baseline survey in March and April 2017, aiming to describe the incidence and characteristics of PARI. PARI experience and physical activity (PA) participation in the past 12 months were collected. Injury incidence density (IID) and risk, and injury characteristics were evaluated for the overall sample and by gender. Pearson chi-square or Fisher's exact tests and independent-sample t tests were used to test between-group differences. We found that 486 PARIs were reported totally by 289 participants, with an overall IID of 0.57 per 1000 hours of exposure (males: 1.07, females: 0.45) and an injury risk of 0.34 injuries/student/y (males: 0.52; females: 0.28). Higher IIDs were found in roller skating, football, and basketball. The majority of injuries occurred outdoors and involved the lower extremities, with sprain and strain being the primary injury types. Moreover, most injuries were new, acute, and happened in non-contact situations. Of all injuries, 52.1% required medical attention and 64.6% resulted in inactivity of one or more days. Some significant differences were observed between males and females. Our study indicates that PARI is a public health concern among Chinese university students, which can provide direction for targeted prophylactic interventions to underpin the sex-specific injury mechanism to reduce PARI.

KNEE PROPRIOCEPTION MAY BE ALTERED BY TREATMENT IN ATHLETES SUFFERING FROM DELAYED ONSET MUSCLE SORENESS

Delayed onset muscle soreness (DOMS) is a very common musculoskeletal problem in athletes involved in extreme competitions. The aim of this study is to compare the effect of diathermy, sham diathermy and massage on the knee proprioception of athletes treated for DOMS. Forty athletes were enrolled after the second day of a demanding ski mountaineering race. They were randomly assigned to four groups: no treatment [Formula: see text], massage [Formula: see text], diathermy [Formula: see text], and sham diathermy [Formula: see text]. The knee reposition error was measured after the treatments in order to assess knee proprioception. Significant differences between the diathermy and sham diathermy groups were found ([Formula: see text]) with an absolute effect size of [Formula: see text]. No other significant differences were found among groups. This means that diathermy has a negative impact on joint proprioception and can be explained by the spindle desensitization consequent to deeper tissue heating. This information can be important in the DOMS management of athletes, since an altered proprioception may interfere with the athlete’s performance and can increase the risk of injury.

Beighton scoring of joint laxity and injury incidence in Middle Eastern male youth athletes: a cohort study

Objectives

To examine the association between generalised joint laxity (GJL) and injury rates in Middle Eastern male youth athletes.

Design

Prospective observational study consisting of GJL screen and injury audit (season 2009/2010).

Setting

Aspire Sports Academy Doha, Qatar.

Participants

A total of 226 adolescent male athletes (mean age: 14.2 years; SD: 1.7; range: 10–18) involved in 15 sporting activities were grouped into contact and non-contact sports. All available athletes were included in this study.

Outcome measures

A seasonal injury audit, athletes’ anthropometric characteristics, for example, weight, height and body mass index and screen for GJL to determine Beighton Score (BS).

Results

The 226 athletes sustained 596 injuries and 75% reported at least one injury over a seasonal injury audit. Players in contact sports were injured more often than players in non-contact sports (more frequent injuries than injury-free time in contact sports; 127 days (95% CI 93 to 160) vs 176 days in non-contact sports (95% CI 118 to 234) (p<0.001). Survival analysis showed that gradient BS was not associated with injury HR=1.004 (95% CI 0.95 to 1.06) in the overall cohort. However, BS was associated with a greater injury risk in contact sports (HR: 1.29; 95% CI 1.05 to 1.59; p=0.015).

Conclusion

Greater GJL, defined by gradient BS, plus involvement in contact sports together influence injury risk in youth athletes. Preseason documentation of GJL scoring should be considered specifically for contact sports as injury pre-emptive measure.

Playing football on artificial turf as a risk factor for fifth metatarsal stress fracture: a retrospective cohort study

OBJECTIVE

The fifth metatarsal stress fracture is a common injury among football players. Although several risk factors have been proposed, the association between the playing surface and development of fifth metatarsal stress fractures (MT-5) has not been evaluated. We conducted an epidemiological study using a computer-based survey to investigate the association between the playing surface and development of MT-5.

METHODS

This study included 1854 football players, of which 41 experienced MT-5 within the past 24 months. Baseline demographic data and the percentage of time spent playing on artificial turf and clay fields were compared between the non-MT-5 and MT-5 player groups, and the risks for development of MT-5 associated with the playing surfaces were estimated by univariate and multivariate analyses.

RESULTS

There were significant differences in body mass index, years of play, playing categories and playing time on artificial turf between non-MT-5 and MT-5 groups (p<0.05). Generalised estimating equations analyses adjusted for multiple confounders demonstrated that relative to the risk of playing <20% of the time on each surface, the OR (OR: 95% CI) for MT-5 for playing on artificial turf >80% of the time increased (3.44: 1.65 to 7.18), and for playing on a clay field 61%-80% of the time, the OR decreased (0.25: 0.11 to 0.59).

CONCLUSIONS

A higher percentage of playing time on an artificial turf was a risk factor for developing MT-5 in football players. This finding could be beneficial for creating strategies to prevent MT-5.

Acute and overuse injuries among sports club members and non-members: the Finnish Health Promoting Sports Club (FHPSC) study

Background

Physical activity in adolescence is promoted for its multi-dimensional health benefits. However, too intensive sports participation is associated with an increased injury risk. Our aim was to compare the occurrence of acute and overuse injuries in Finnish sports club members and non-members and to report training and competing habits associated with a higher injury risk in sports club members.

Methods

In this cross-sectional survey targeted at 14–16-year-old adolescents, a structured questionnaire was completed by 1077 sports club members and 812 non-members. The main outcome measures were self-reported acute and overuse injuries, their location and type.

Results

At least one acute injury in the past year was reported by 44.0% of sports club members and 19.8% of non-members (P < 0.001). The sex-adjusted odds ratio (OR) for acute injury in sports club members compared to non-members was 3.13 (95% confidence interval (95% CI) 2.54–3.87). Thirty-five percent of sports club members and 17.4% of non-members (P < 0.001) reported at least one overuse injury during the past year. The overuse injury OR for sports club members was 2.61 (95% CI 2.09–3.26). Sports club members who trained 7–14 h per week during training (OR 1.61, 95% CI 1.21–2.12, P = 0.001) or competition season (OR 1.55, 95% CI 1.18–2.06, P = 0.002) were more likely to report an injury compared to members who trained 3–6 h per week. Those sports club members who participated in forty competitions or more compared to 7–19 competitions per year were more likely to report an acute injury (OR 1.55, 95% CI 1.05–2.08, P = 0.028) or for an overuse injury (OR 1.53, 95% CI 1.02–2.30, P = 0.038).

Conclusions

Both acute and overuse injuries are common among youth sports club members, and the number increases along with increasing amounts of training and competitions. More effective injury prevention is needed both for adolescents engaging in sports club activities and for other adolescents.

Electronic supplementary material

The online version of this article (10.1186/s12891-019-2417-3) contains supplementary material, which is available to authorized users.

Risk models for lower extremity injuries among short- and long distance runners: A prospective cohort study

BACKGROUND

Running injuries are very common. Risk factors for running injuries are not consistently described across studies and do not differentiate between runners of long- and short distances within one cohort.

OBJECTIVES

The aim of this study is to determine risk factors for running injuries in recreational long- and short distance runners separately.

DESIGN

A prospective cohort study.

METHODS

Recreational runners from four different running events are invited to participate. They filled in a baseline questionnaire assessing possible risk factors about 4 weeks before the run and one a week after the run assessing running injuries. Using logistic regression we developed an overall risk model and separate risk models based on the running distance.

RESULTS

In total 3768 runners participated in this study. The overall risk model contained 4 risk factors: previous injuries (OR 3.7) and running distance during the event (OR 1.3) increased the risk of a running injury whereas older age (OR 0.99) and more training kilometers per week (OR 0.99) showed a decrease. Models between short- and long distance runners did not differ significantly. Previous injuries increased the risk of a running injury in all models, while more training kilometers per week decreased this risk.

CONCLUSIONS

We found that risk factors for running injuries were not related to running distances. Previous injury is a generic risk factor for running injuries, as is weekly training distance. Prevention of running injuries is important and a higher weekly training volume seems to prevent injuries to a certain extent.

A Comparison of Bone Marrow and Cord Blood Mesenchymal Stem Cells for Cartilage Self-Assembly

Joint injury is a common cause of premature retirement for the human and equine athlete alike. Implantation of engineered cartilage offers the potential to increase the success rate of surgical intervention and hasten recovery times. Mesenchymal stem cells (MSCs) are a particularly attractive cell source for cartilage engineering. While bone marrow-derived MSCs (BM-MSCs) have been most extensively characterized for musculoskeletal tissue engineering, studies suggest that cord blood MSCs (CB-MSCs) may elicit a more robust chondrogenic phenotype. The objective of this study was to determine a superior equine MSC source for cartilage engineering. MSCs derived from bone marrow or cord blood were stimulated to undergo chondrogenesis through aggregate redifferentiation and used to generate cartilage through the self-assembling process. The resulting neocartilage produced from either BM-MSCs or CB-MSCs was compared by measuring mechanical, biochemical, and histological properties. We found that while BM constructs possessed higher tensile properties and collagen content, CB constructs had superior compressive properties comparable to that of native tissue and higher GAG content. Moreover, CB constructs had alkaline phosphatase activity, collagen type X, and collagen type II on par with native tissue suggesting a more hyaline cartilage-like phenotype. In conclusion, while both BM-MSCs and CB-MSCs were able to form neocartilage, CB-MSCs resulted in tissue more closely resembling native equine articular cartilage as determined by a quantitative functionality index. Therefore, CB-MSCs are deemed a superior source for the purpose of articular cartilage self-assembly.

Risk Factors for Lower Extremity Overuse Injuries in Female Youth Soccer Players

Background:

Youth soccer injuries are common and of increasing concern, with sport specialization occurring at younger ages. Limited research is available regarding overuse injuries and risk factors in young female athletes.

Purpose:

To identify the number and rate of overuse injuries in female soccer players (ages 12-15 years), describe the anatomic location and type of injury, and evaluate contributing risk factors.

Study Design:

Case-control study; Level of evidence, 3.

Methods:

A total of 351 female youth soccer players, ages 12 to 15 years, from Washington State were evaluated from 2008 to 2012. Players with lower extremity overuse injuries were identified through weekly emails and were interviewed by telephone to obtain data on injury type and body region. We evaluated the association between overuse injuries and preseason risk factors, including joint hypermobility, hip and knee muscle strength, and jump biomechanics, using Poisson regression to estimate relative risk (RR) and 95% CIs.

Results:

The incidence rate for first-time lower extremity overuse injuries was 1.7 per 1000 athlete-exposure hours (AEH; 95% CI, 1.4-2.2), and that for repeat injuries was 3.4 per 1000 AEH (95% CI, 2.1-5.6). Knee injuries accounted for 47% of overuse injuries. Increased valgus was associated with a 3.2-fold increased risk (95% CI, 1.52-6.71) for knee injury. A 1–standard deviation (SD) increase in hamstring strength was associated with a 35% decreased risk (RR, 0.65; 95% CI, 0.46-0.91) for overuse knee injuries, and a 1-SD increase in quadriceps strength was associated with a 30% decreased risk (RR, 0.70; 95% CI, 0.50-0.98). A 1-SD increase in hip flexor strength was associated with a 28% decreased risk (RR, 0.72; 95% CI, 0.51-1.00) for overuse knee injuries, and a 1-SD increase in external rotation strength was associated with a 35% decreased risk (RR, 0.65; 95% CI, 0.46-0.91). Playing on more than 1 soccer team was associated with a 2.5-fold increased risk (95% CI, 1.08-5.35) for overuse knee injuries, and participating in other physical activities was associated with a 61% decreased risk (odds ratio, 0.39; 95% CI, 0.15-0.81).

Conclusion:

In this study, lower extremity overuse injuries in female youth soccer players affected primarily the knee. Lower knee separation distance, decreased lower extremity strength, and playing on more than 1 soccer team increased injury risk.

Comparing spinal manipulation with and without Kinesio Taping® in the treatment of chronic low back pain

OBJECTIVES

Chronic non-specific low back pain (CNLBP) is a prevalent problem among athletes that can cause long-lasting disability and time lost from sporting activities. Thus far, a variety of methods have been suggested to address this problem, including spinal manipulation (SM) and Kinesio Tape^® (KT). The aim of this study was to investigate whether adding KT to SM can provide any extra effect in athletes with CNLBP or not.

METHOD

Forty-two athletes (21males, 21females) with CNLBP were randomized into two groups of SM (n = 21) and SM plus KT (n = 21). Pain intensity, functional disability level and trunk flexor-extensor muscles endurance were assessed by Numerical Rating Scale (NRS), Oswestry pain and disability index (ODI), McQuade test, and unsupported trunk holding test, respectively. The tests were done before and immediately, one day, one week, and one month after the interventions and compared between the two groups.

RESULTS

After treatments, pain intensity and disability level decreased and endurance of trunk flexor-extensor muscles increased significantly in both groups. Repeated measures analysis, however, showed that there was no significant difference between the groups in any of the evaluations.

CONCLUSIONS

The findings of the present study showed that adding KT to SM does not appear to have a significant extra effect on pain, disability and muscle endurance in athletes with CNLBP. However, more studies are needed to examine the therapeutic effects of KT in treating these patients. CLINICAL TRIAL REGISTRY NUMBER (IRCT.IR): IRCT2016020624149N5.

Effects of eccentric overload training on patellar tendon and vastus lateralis in three days of consecutive running

BACKGROUND

The analysis of structural changes in patellar tendon and muscle of healthy subjects in response to mechanical loads provides useful insight into the mechanism underlying overuse injuries.

METHODS

Changes produced in tendon and muscles structures after eccentric overload training and three consecutive running days were examined. Twenty healthy subjects were recruited and divided into two groups. One group (ECC) performed eccentric overload squat training (six weeks). After such training, the ECC group performed three running sessions on consecutive days, as did the control group (CONT). The structure of their patellar tendons and vastus lateralis muscles was quantified using ultrasound and Doppler imaging. Images were obtained before and after eccentric training for the ECC group and on every day of running performance for both groups.

RESULTS

After eccentric training, the ECC group experienced an increase in cross-sectional area (CSA) of patellar tendon (P=0.012). After every day of running, the ECC group experienced a decrease in CSA (P=0.027). In the CONT group, after one day of running a significant increase was observed in anteroposterior width of their patellar tendon (P=0.028), as well as a decrease in pennation angle of vastus lateralis muscle (P=0.028) within three days of running sessions.

CONCLUSIONS

Eccentric overload training brought about changes in the patellar tendon consistent with an improvement in the quality of the tissue. The ECC group in our study showed a more normalised pattern than the CONT group in the running performance, in agreement with previous research.

LEVEL OF EVIDENCE

Level 3, controlled trial.

Short-Term Absenteeism and Health Care Utilization Due to Lower Extremity Injuries Among Novice Runners: A Prospective Cohort Study

OBJECTIVE

To describe absenteeism and health care utilization (HCU) within 6 weeks after occurrence of running-related injuries (RRIs) among novice runners and to explore differences relating to injury and personal characteristics.

DESIGN

Prospective cohort study.

SETTING

Primary care.

PARTICIPANTS

One thousand six hundred ninety-six novice runners (18-65 years) participating in a 6-week running program ("Start-to-Run").

MAIN OUTCOME MEASURES

Injury characteristics were assessed by weekly training logs and personal characteristics by a baseline questionnaire. Data on absenteeism and HCU were collected using questionnaires at 2 and 6 weeks after the RRI occurred.

RESULTS

A total of 185 novice runners (11%) reported an RRI during the 6-week program. Of these injured novice runners, 78% reported absence from sports, whereas only 4% reported absence from work. Fifty-one percent of the injured novice runners visited a health care professional, mostly physical therapists (PTs) rather than physicians. Absenteeism was more common among women than men and was also more common with acute RRIs than gradual-onset RRIs. As regards HCU, both the variety of professionals visited and the number of PT visits were higher among runners with muscle-tendon injuries in the ankle/foot region than among those with other RRIs.

CONCLUSIONS

Among novice runners sustaining an RRI during a 6-week running program, over three quarters reported short-term absence from sports, whereas absence from work was very limited, and over half used professional health care. Both absence and HCU are associated with injury characteristics.

CLINICAL RELEVANCE

In future running promotion programs (eg in Start-to-Run programs), specific attention should be paid to acute injuries and to muscle-tendon injuries in the ankle/foot region.

Thermographic Assessment of Eccentric Overload Training Within Three Days of a Running Session

The aim of this study was to analyze the changes in patellar and Achilles tendons between a group trained using eccentric overload and an untrained group within 3 days of a running session. To this end, infrared thermography (IRT) will be used. Twenty healthy male subjects were divided into 2 groups. One group performed a 6-week squat training in the flywheel before the running session. During the running intervention, both groups ran in 3 different days, for 1 hour each, at 80% maximal heart rate. Before, just after, and after 10 minutes of the running intervention, participants were assessed using IRT. Eccentrically trained groups showed a statistically significant difference (analysis of variance, p = 0.0049) expressed as a smaller bilateral increase in temperature in the patellar tendon just before the first running day (right side, 0.11 °C; left side, 0.29 °C). On the other days of running and in the Achilles tendon groups, similar changes were observed: an increase in the temperature after running and no significant difference between contralateral limbs. Our results point at eccentric overload training providing a better adaptation for the first day of running. IRT is an easy-to-apply noninvasive tool to analyze and compare the effects of performance on tendon tissues.

Minimalist Running Shoes and Injury Risk Among United States Army Soldiers

BACKGROUND

Minimalist running shoes (MRS) are lightweight, are extremely flexible, and have little to no cushioning. It has been thought that MRS will enhance running performance and decrease injury risk.

PURPOSE

To compare physical characteristics, fitness performance, and injury risks associated with soldiers wearing MRS and those wearing traditional running shoes (TRS).

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Participants were men in a United States Army brigade (N = 1332). Physical characteristics and Army Physical Fitness Test data were obtained by survey. Fitness performance testing was administered at the brigade, and the types of footwear worn were identified by visual inspection. Shoe types were categorized into 2 groups: TRS (stability, cushioning, and motion control) and MRS. Injuries from the previous 12 months were obtained from the Defense Medical Surveillance System. A t test was used to determine mean differences between personal characteristics, training, and fitness performance metrics by shoe type. Hazard ratios and 95% CIs were calculated to determine injury risk by shoe type, controlling for other risk factors.

RESULTS

A majority of soldiers wore cushioning shoes (57%), followed by stability shoes (24%), MRS (17%), and motion control shoes (2%). Soldiers wearing MRS were slightly younger than those wearing TRS (P < .01); performed more push-ups, sit-ups, and pull-ups (P < .01); and ran faster during the 2-mile run (P = .01). When other risk factors were controlled, there was no difference in injury risk for running shoe type between soldiers wearing MRS compared with TRS.

CONCLUSIONS

Soldiers who chose to wear MRS were younger and had higher physical performance scores compared with soldiers wearing TRS. When these differences are controlled, use of MRS does not appear to be associated with higher or lower injury risk in this population.

Injuries and Associated Risk Factors Among Adolescent Elite Orienteerers: A 26-Week Prospective Registration Study

CONTEXT

In orienteering, the number of injury-registration studies is limited. Most researchers have used a cross-sectional design during specific events and, therefore, have mainly identified acute injuries.

OBJECTIVE

To determine the prevalence of injuries by registering acute and overuse injuries in adolescent elite orienteerers over 26 weeks and to study the variation of injury prevalence over the season and the potential risk factors.

DESIGN

Cohort study.

SETTING

Two high schools in Sweden with national orienteering teams.

PATIENTS OR OTHER PARTICIPANTS

All athletes (33 adolescent girls, 31 adolescent boys; age = 17 ± 1 years) from 2 high schools with orienteering teams.

MAIN OUTCOME MEASURE(S)

We used a weekly Web-based questionnaire to identify the incidence and prevalence of injuries and training variables. Risk factors for injury were calculated using multiple linear regression techniques.

RESULTS

The average weekly prevalence of overuse and acute injuries was 35.7% (95% confidence interval = 34.8%, 36.6%) and 1.7% (95% confidence interval = 1.3%, 2.1%), respectively; overuse injuries (78.0%, n = 85) accounted for the majority. The incidence of acute and overuse injuries was highest for the foot/lower leg (48.6%, n = 53), and 71.6% (n = 78) of all injuries affected the foot/lower leg and knee area. Time to the first reported injury was associated with training volume (β = 0.184, P = .001), competition time (β = -0.701, P = .009), running on asphalt roads (β = -0.348, P = .008), and running on forest surfaces and trails (β = -0.331, P = .007), with a model fit of r( 2) = 0.50 (intercept = 2.196, P < .001). During the study, we observed a weekly increase (0.3%) in the prevalence of overuse injuries in the foot/lower leg (r( 2) = 0.33, P = .001); the highest prevalence (26.9%) was at the beginning of the competitive season.

CONCLUSIONS

Overuse injuries, predominately in the foot/lower leg area, were more common than acute injuries in adolescent elite orienteerers. These injuries had the highest prevalence at the beginning of the competitive season; therefore, this period can be seen as a possible risk factor for sustaining overuse injuries in the foot/lower leg.

Spinal alignment, mobility of the hip and thoracic spine and prevalence of low back pain in young elite cross-country skiers

This study investigated the association between spinal alignment, mobility of the hips and the thoracic spine and low back pain in adolescent cross-country skiers. Cohort of 51 elite cross-country skiers from a cross-country skiing high school in Sweden participated in the study. Sagittal spinal alignment, active range of motion in flexion, extension and rotation of the thoracic spine as well as passive and active extension of the hips were measured. The participants also completed a questionnaire regarding training, competition, skiing technique and occurrence of low back pain. A simple linear regression was calculated to predict pain score based on thoraco-lumbar relation, with a significant (P<0.05) regression equation of y=-0.069x+2.280 (standard error of estimate, 0.034). Participants with greater lordosis than kyphosis were more likely to suffer from low back pain than subjects without this offset. Thoracic mobility and passive or active hip extension showed no correlation with low back pain. Sagittal spinal alignment seems to be related with low back pain among young elite cross-country skiers. This study shows that range of motion of the thoracic spine and hips do not have an effect on the prevalence of low back pain in this population.

Health promotion activities of sports clubs and coaches, and health and health behaviours in youth participating in sports clubs: the Health Promoting Sports Club study

Introduction

Sports clubs form a potential setting for health promotion, but the research is limited. The aim of the Health Promoting Sports Club (HPSC) study was to elucidate the current health promotion activities of youth sports clubs and coaches, and to investigate the health behaviours and health status of youth participating in sports clubs compared to non-participants.

Methods and analysis

The study design employs cross-sectional multilevel and multimethod research with aspirations to a prospective cohort study in the next phase. The setting-based variables at sports clubs and coaching levels, and health behaviour variables at the individual level, are investigated using surveys; and total levels of physical activity are assessed using objective accelerometer measurements. Health status variables will be measured by preparticipation screening. The health promotion activity of sports clubs (n=154) is evaluated by club officials (n=313) and coaches (n=281). Coaches and young athletes aged 14–16 (n=759) years evaluate the coaches’ health promotion activity. The survey of the adolescents’ health behaviours consist of two data sets—the first is on their health behaviours and the second is on musculoskeletal complaints and injuries. Data are collected via sports clubs (759 participants) and schools 1650 (665 participants and 983 non-participants). 591 (418 athletes and 173 non-athletes) youth, have already participated in preparticipation screening. Screening consists of detailed personal medical history, electrocardiography, flow-volume spirometry, basic laboratory analyses and health status screening, including posture, muscle balance, and static and dynamic postural control tests, conducted by sports and exercise medicine specialists.

Ethics and dissemination

The HPSC study is carried out conforming with the declaration of Helsinki. Ethical approval was received from the Ethics Committee of Health Care District of Central Finland. The HPSC study is close-to-practice, which generates foundations for development work within youth sports clubs.

Low back pain in female elite football and handball players compared with an active control group

PURPOSE

The purpose of this cross-sectional study was to compare the prevalence of low back pain (LBP) among female elite football and handball players to a matched non-professional active control group.

METHODS

The participants were requested to answer a questionnaire based on standardized Nordic questionnaires for musculoskeletal symptoms to assess the prevalence of LBP. Included participants were elite female football (n = 277) and handball players (n = 190), and a randomly selected control group from the Norwegian population (n = 167).

RESULTS

Fifty-seven percentage of the football players, 59 % of the handball players and 60 % of the control group had experienced LBP the previous year. There were no significant group differences in the prevalence of LBP ever (p = 0.62), the previous year (p = 0.85) or the previous 7 days (p = 0.63). For both sports, there was a significant increase in prevalence of LBP from the resting period to the competitive periods of the season (p ≤ 0.001). Seventy percent of the goalkeepers in both football and handball had experienced LBP the previous year.

CONCLUSION

There were no difference in LBP among female elite football and handball players compared with the control group. However, female elite athletes in football and handball reported a high prevalence of LBP compared to previous studies. The variations in LBP and playing positions indicate that specific field positions, in football and handball, is a risk factor for developing LBP.

Self-reported previous knee injury and low knee function increase knee injury risk in adolescent female football

Knee injuries are common in adolescent female football. Self-reported previous knee injury and low Knee injury and Osteoarthritis Outcome Score (KOOS) are proposed to predict future knee injuries, but evidence regarding this in adolescent female football is scarce. The aim of this study was to investigate self-reported previous knee injury and low KOOS subscale score as risk factors for future knee injuries in adolescent female football. A sample of 326 adolescent female football players, aged 15-18, without knee injury at baseline, were included. Data on self-reported previous knee injury and KOOS questionnaires were collected at baseline. Time-loss knee injuries and football exposures were reported weekly by answers to standardized text-message questions, followed by injury telephone interviews. A priori, self-reported previous knee injury and low KOOS subscale scores (< 80 points) were chosen as independent variables in the risk factor analyses. The study showed that self-reported previous knee injury significantly increased the risk of time-loss knee injury [relative risk (RR): 3.65, 95% confidence (CI) 1.73-7.68; P < 0.001]. Risk of time-loss knee injury was also significantly increased in players with low KOOS subscale scores (< 80 points) in Activities of Daily Living (RR: 5.0), Sport/Recreational (RR: 2.2) and Quality of Life (RR: 3.0) (P < 0.05). In conclusion, self-reported previous knee injury and low scores in three KOOS subscales significantly increase the risk of future time-loss knee injury in adolescent female football.

Overuse injuries in youth basketball and floorball

Background

The popularity of team sports is growing among young people. High training volume and intensity may predispose young athletes to overuse injuries. Research to date has tended to focus on acute injuries rather than overuse injuries. The purpose of this study was to examine the occurrence, nature, and severity of overuse injuries in youth basketball and floorball, with the hypothesis that overuse injuries are frequent in youth team sports.

Methods

The study comprised a total of 401 Finnish team sports athletes (207 basketball and 194 floorball players). The data were collected using a detailed questionnaire. The participants (mean age 15.8±1.9 years) responded to the questionnaire covering information on overuse injuries during the previous 12 months.

Results

A total of 190 overuse injuries was reported (97 in basketball and 93 in floorball). In both sports, most of the injuries involved the lower extremities (66% and 55% of all injuries in basketball and floorball, respectively). In basketball, the most commonly injured site was the knee (44 cases, 45%). In floorball, the most commonly injured sites were the lower back/pelvis (36 cases, 39%) and knee (32 cases, 34%). Overuse injuries caused an average time loss from full participation of 26±50 (median 7) days in basketball and 16±37 (median 5) days in floorball.

Conclusion

Overuse injuries are a common problem in youth team sports, and often cause long-term absence from full participation. The findings suggest that injury reduction and training load monitoring strategies are needed in the field. More research using explicit prospective data collection is needed to better understand the problem.

Epidemiology of overuse injuries among high-school athletes in the United States

OBJECTIVE

To examine high school overuse injury rates and patterns by sex and sport.

STUDY DESIGN

High school athletes participating in the High School Reporting Information Online study were examined in a descriptive epidemiologic study. Overuse injury data for the 2006/2007-2011/2012 academic years collected via High School Reporting Information Online from a large national sample of US high schools where certified athletic trainers completed detailed injury reports were evaluated.

RESULTS

From 2006/2007 to 2011/2012, a total of 2834 overuse injuries were reported during 18 889 141 athletic exposures (1.50 per 10 000 athletic exposures). Girls had greater rates of overuse injury (1.88) than boys (1.26) (rate ratio 1.50, 95% CI 1.39-1.61). The greatest rates were in girls' track and field (3.82) and girls' field hockey (2.93). Overuse injuries represented 7.7% of all injuries, ranging from a low of 1.4% of all boys' ice hockey injuries to a high of 55.7% of all boys' swimming and diving injuries. Overall, overuse injuries were evenly distributed across athletes in each year of high school (freshman, 25.6%; sophomore, 25.3%; junior, 24.9%; senior, 24.3%). However, there were distinct differences by sex. The most frequent site of injury was the lower leg (21.8%). Injuries most frequently resulted in time loss of less than 1 week (50.0%), with only 7.6% resulting in time loss greater than 3 weeks.

CONCLUSIONS

Overuse injury patterns differed by sex and sport. A better understanding of overuse injury patterns and criteria for return to play may help direct preventative measures and injury management.

Risk factors for lower extremity injuries among half marathon and marathon runners of the Lage Landen Marathon Eindhoven 2012: A prospective cohort study in the Netherlands

To determine risk factors for running injuries during the Lage Landen Marathon Eindhoven 2012. Prospective cohort study. Population-based study. This study included 943 runners. Running injuries after the Lage Landen Marathon. Sociodemographic and training-related factors as well as lifestyle factors were considered as potential risk factors and assessed in a questionnaire 1 month before the running event. The association between potential risk factors and injuries was determined, per running distance separately, using univariate and multivariate logistic regression analysis. In total, 154 respondents sustained a running injury. Among the marathon runners, in the univariate model, body mass index ≥ 26 kg/m(2), ≤ 5 years of running experience, and often performing interval training, were significantly associated with running injuries, whereas in the multivariate model only ≤ 5 years of running experience and not performing interval training on a regular basis were significantly associated with running injuries. Among marathon runners, no multivariate model could be created because of the low number of injuries and participants. This study indicates that interval training on a regular basis may be recommended to marathon runners to reduce the risk of injury.

High injury incidence in adolescent female soccer

BACKGROUND

Previous studies report varying rates of time-loss injuries in adolescent female soccer, ranging from 2.4 to 5.3 per 1000 athlete-exposures or 2.5 to 3.7 per 1000 hours of exposure. However, these studies collected data using traditional injury reports from coaches or medical staff, with methods that significantly underestimate injury rates compared with players' self-reports.

PURPOSE

The primary aim was to investigate the injury incidence in adolescent female soccer using self-reports via mobile telephone text messaging. The secondary aim was to explore the association between soccer exposure, playing level, and injury risk.

STUDY DESIGN

Descriptive epidemiology study and cohort study; Level of evidence, 2 and 3.

METHODS

During a full adolescent female soccer season in Denmark (February-June 2012), a population-based sample of 498 girls aged 15 to 18 years was included in the prospective registration of injuries. All players were enrolled on a team participating in Danish Football Association series. Soccer injuries and exposure were reported weekly by answers to standardized text message questions, followed by individual injury interviews. Soccer exposure and playing levels were chosen a priori as the only independent variables of interest in the risk factor analyses. Injury rates and relative risks were estimated using Poisson regression. Generalized estimation equations were used to take into account that players were clustered within teams.

RESULTS

There were 498 players who sustained a total of 424 soccer injuries. The incidence of injuries was 15.3 (95% CI, 13.1-17.8), the incidence of time-loss injuries was 9.7 (95% CI, 8.2-11.4), and the incidence of severe injuries was 1.1 (95% CI, 0.7-1.6) per 1000 hours of soccer exposure. Higher average exposure in injury-free weeks was associated with a lower injury risk (P value for trend <.001), and players with low exposure (≤1 h/wk) were 3 to 10 times more likely to sustain a time-loss injury compared with other players (P < .01). Playing level was not associated with the risk of time-loss injuries (P = .18).

CONCLUSION

The injury incidence in adolescent female soccer is high, and this includes many severe injuries. Players with low soccer participation (≤1 h/wk) have a significantly higher injury risk compared with players participating more frequently.

Pediatric sports injuries: a comparison of males versus females

BACKGROUND

There is still much that we do not know about differences in sports injuries between young male and female athletes and the factors that may increase the risk for injuries in this regard.

PURPOSE

To describe and compare differences between males and females in pediatric sports-related injuries.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

A retrospective chart review was performed using a 5% random sampling (N = 2133) of medical records of children aged 5 to 17 years seen over 10 years in a sports medicine clinic at a large academic pediatric hospital. Information was collected and analyzed on age, sex, height, weight, injury type (overuse vs acute/traumatic), location of injury, and sports involvement.

RESULTS

Overall, female athletes had a higher percentage of overuse injuries (62.5%) compared with traumatic injuries (37.5%); the opposite was seen in male athletes (41.9% vs. 58.2%, respectively; P < .001). Looking at specific areas of injury, female athletes sustained more injuries to the lower extremity (65.8%) and spine (11.3%) as compared with male athletes (53.7% and 8.2%, respectively). Male patients had a greater percentage of injuries to the upper extremity (29.8%) as compared with female patients (15.1%). The type of hip/pelvis injuries differed greatly by sex, with females sustaining more overuse (90.9%) and soft tissue injuries (75.3%) versus males, who suffered injuries that tended to be traumatic (58.3%) and bony (55.6%) in nature. Males were more likely than females to participate in team and contact/collision sports. The percentage of females with patellofemoral knee pain was approximately 3 times greater than that of males (14.3% vs. 4.0%, respectively; P < .001). Males were twice as likely as females to be diagnosed with osteochondritis dissecans (8.6% vs. 4.3%, respectively; P < .001) and fractures (19.5% vs. 8.2%, respectively; P < .001). The percentage of males and females who sustained an anterior cruciate ligament injury was almost equal (10.0% and 8.9%, respectively; P = .369).

CONCLUSION

Sports injuries in young males and females differed by injury type, diagnosis, and body area. These results may be related to the referral patterns unique to the division of the hospital, including a high number of female dancers. Further investigation is required to better understand the injury risk in pediatric male and female athletes.

Epidemiology of musculoskeletal injuries in a population of harness Standardbred racehorses in training

Background

There is a substantial paucity of studies concerning musculoskeletal injuries in harness Standardbred racehorses. Specifically, little is known about the epidemiology of exercise-related musculoskeletal injuries. Most studies on this subject involve Thoroughbred racehorses, whose biomechanics and racing speed differ from Standardbred, making comparisons difficult. Here, a population of Standardbred racehorses trained at the same racecourse was studied over four years and a classification system for exercise-related musculoskeletal injuries was designed. The incidence rates of musculoskeletal injuries causing horses’ withdrawal from training for 15 days or longer were investigated. A mixed-effects Poisson regression model was used to estimate musculoskeletal injury rates and to describe significance of selected risk factors for exercise-related injuries in this population.

Results

A total of 356 trotter racehorses from 10 different stables contributed 8961 months at risk of musculoskeletal injuries. Four-hundred-and-twenty-nine injuries were reported and classified into 16 categories, based on their aetiology and anatomical localisation. The overall exercise-related injury rate was 4.79 per 100 horse months. When considering risk factors one by one in separate univariable analyses, we obtained the following results: rates did not differ significantly between genders and classes of age, whereas one driver seemed to cause fewer injuries than the others. Racing speed and racing intensity, as well as recent medical history, seemed to be significant risk factors (p < 0.001), while being shod or unshod during racing was not. On the other hand, when pooling several risk factors in a multivariable approach, only racing intensity turned out to be significant (p < 0.001), since racing speed and the racing intensity were partially confounded, being strongly correlated to one another.

Conclusion

Characterizing epidemiology of exercise-related musculoskeletal injuries in trotter racehorses provides baseline incidence rate values. Incidence rates of stress fracture are lower in Standardbreds compared to Thoroughbreds, whereas the opposite is true for tendon and suspensory ligament injuries. In addition to identification of risk factors for musculoskeletal injuries among Standardbred racehorses, results suggest that racing intensity seems to be a protective predictor of risk and recent medical history could be used to identify horses at risk of injury.